kvm: x86: Add XCR0 support for Intel AMX

mainline inclusion
from mainline-v5.17-rc1
commit 86aff7a4
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I5RQLJ


CVE: NA

Intel-SIG: commit 86aff7a4 kvm: x86: Add XCR0 support for Intel AMX.

--------------------------------

Two XCR0 bits are defined for AMX to support XSAVE mechanism. Bit 17
is for tilecfg and bit 18 is for tiledata.

The value of XCR0[17:18] is always either 00b or 11b. Also, SDM
recommends that only 64-bit operating systems enable Intel AMX by
setting XCR0[18:17]. 32-bit host kernel never sets the tile bits in
vcpu->arch.guest_supported_xcr0.

Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20220105123532.12586-16-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Lin Wang <lin.x.wang@intel.com>